It is a common reason for children to present to health care professionals. Interpretation of these events can be challenging.

The doctor is initially presented with a description of a seizure type. It is important to identify the seizure type and collect information such as its time of occurrence, frequency, age of onset. Using this information together with the EEG, a diagnosis of a particular childhood epilepsy syndrome should be reached upon which management can be based.

The importance of the interictal EEG is emphasized in syndrome classification. An MRI is the imaging test of choice and is important in epilepsies where a structural abnormality is suspected. The yield in genetic epilepsy is low.

The International League Against Epilepsy (ILAE) is closely involved in the classification of Seizures and Epilepsies. Children should have a diagnosis in keeping with this classification. 

The following documents provide detailed information on the revised classification of seizure types and epilepsy syndromes by the ILAE in 2017:

• Fisher et al. (2017): Operational classification of seizure types by the International League Against Epilepsy: Position Paper of the ILAE Commission for Classification and Terminology
• Fisher et al. (2017): Instruction manual for the ILAE 2017 operational classification of seizure types
• Scheffer et al. (2017): ILAE classification of the epilepsies: Position paper of the ILAE Commission for Classification and Terminology

In 2014, the ILAE Commission on Classification and Terminology also released an online Diagnostic Manual for Epilepsy, called epilepsydiagnosis.org which provides further useful information.

The International League Against Epilepsy (2011-2013) classified seizures into three groups:

• Generalised
• Focal
• Unknown

This document provides detailed information on the revised classification of seizure types by the ILAE in 2017.

Generalised seizures include:

• Generalised tonic clonic
• Absence
• Clonic
• Tonic
• Atonic
• Myoclonic

Generalised Tonic Clonic seizures

• There is an initial tonic phase in which there is brief tonic flexion of axial muscles then longer tonic extension.
• This is followed by an intermediary phase of vibratory tremor.
• The clonic phase consists of alternating contraction and atonia or inhibition. Expiratory grunts and tongue biting may occur in this phase.
• Finally, there is a second brief tonic phase in which again tongue biting may occur.
• In the postictal phase the patient may be unconscious for a period and respiration compromised.
• During a generalised tonic clonic seizure, there may be marked autonomic features.

Tonic seizures

• May be subtle with only eyelid opening and upward eye deviation.
• In an axial tonic seizure, there is rigidity of posterior neck, paraspinal and abdominal muscles.
• The tonic activity may involve limb contraction leading to falls. Consciousness is abolished during attacks but the events may be very brief from seconds or last approximately a minute.
• The average length is about 10 seconds.
• Tonic seizures are activated by non-REM sleep.

Myoclonic seizures

• There is a sudden involuntary shock-like muscle contraction. The seizure may be focal or regional.
• Jerks may be single, repetitive, rhythmical or arrythmical.
• An inhibitory form of myoclonus has been described known as epileptic negative myoclonus.
• Myoclonic seizures may originate at any level of the nervous system, cortex, cerebellum, brainstem or spinal cord.

Absence seizures

• Classically there is impairment of consciousness.
• There may be subtle other features including mild clonic components, tonic components, atonic components, automatisms or autonomic components.
• Absence seizures are characteristically seen in genetic generalised epilepsies. 

Focal seizures 

• Originate within networks limited to one hemisphere.
• In focal seizures, symptoms and signs may arise from limited involvement of the cortex. Examples are somatosensory, autonomic, psychic and motor focal seizures.
• The revised ILAE terminology describes focal seizures according to one or more specific features: level of awareness/responsiveness, motor, autonomic, or subjective features (i.e. auras).
• Previously, the term ‘simple partial’ seizure was used when consciousness was preserved, and the term ‘complex partial’ seizure was employed when awareness and responsiveness were altered.
• A focal seizure may evolve to a bilateral convulsive seizure.
• New terminology example: Under the revised ILAE classification, a "complex partial seizure with secondary generalization" would now be described as: "a focal seizure with loss of awareness, evolving to a bilateral convulsive seizure".

The NICE Guideline: Epilepsies in Children, Young People and Adults [NG217] was first released in October 2004, with a further publication in January 2012 and updates in February 2016, February 2020, and the latest in April 2022. This is a UK-based guideline and therefore requires some interpretation for the NSW context.

Key points:

• All children with a recent onset suspected seizure should be seen urgently (within 2 weeks) by a specialist. This is to ensure precise and early diagnosis and initiation of therapy as appropriate to their needs.
• The seizure type(s) and epilepsy syndrome, aetiology and co-morbidity should be determined.
• All children with epilepsy should have a comprehensive care plan (see: Epilepsy Management Pack) that is agreed between the individuals, their family and/or carers as appropriate, and primary and secondary care providers.
• The AED (anti-epileptic drug) treatment plan should be individualised according to the seizure type, epilepsy syndrome, co-medication and co-morbidity, the individual’s lifestyle, and the preferences of the individual, their family and/or carers as appropriate.
• All children with epilepsy should have a regular structured review. In children, this review should be carried out at least yearly (but may be between 3 and 12 months by arrangement) by a specialist.
• At the review, individuals should have access to: written and visual information; counselling services; information about voluntary organisations; epilepsy specialist nurses; timely and appropriate investigations; referral to tertiary services, including surgery if appropriate.
• If seizures are not controlled and/or there is diagnostic uncertainty or treatment failure, individuals should be referred to tertiary services soon (within 4 weeks) for further assessment.

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